Abstract: Beam intercept profiles are measured as a particle beam transversely scans across a probe. A current of beam particles, a detector intensity, or image pixel intensities can variously be measured to obtain the profiles. Multiple profiles are used to determine geometric parameters which in turn can be used to configure equipment. In one application, transverse beam intercept profiles are measured for different waist heights of the particle beam. Steepness of the several profiles can be used to determine a height of the probe as the height at which the profile is steepest. The known probe height enables placing the probe in contact with a substrate at another known height. In another application, transverse beam intercept profiles of orthogonal probe edges are used to position a beam waist, reduce spot size, or reduce astigmatism. Techniques are applicable to SEM, FIB, and nanoprobe systems. Methods and apparatus are disclosed, with variations.

Abstract: Apparatus and methods are disclosed for particle beam focusing, suitable for use in sample preparation or test environments, including SEM-based nanoprobing platforms. With a particle beam incident on a sample surface, stage current is used as an indicator of spot size. By scanning or searching settings of a working distance control, a control value having maximum (or minimum) stage current is used to set the beam waist at the sample surface. Alternatively, minima (or maxima) of reflected current can be used. Stigmator controls can be adjusted similarly to reduce astigmatism. The scan of control settings can be performed concurrently with sweeping the beam across a region of interest on the sample. Curved sweep patterns can be used. Energy measurements can be used as an alternative to current measurement. Applications to a nanoprobing workflow are disclosed.

Abstract: Apparatus and methods are disclosed for particle beam focusing, suitable for use in sample preparation or test environments, including SEM-based nanoprobing platforms. With a particle beam incident on a sample surface, stage current is used as an indicator of spot size. By scanning or searching settings of a working distance control, a control value having maximum (or minimum) stage current is used to set the beam waist at the sample surface. Alternatively, minima (or maxima) of reflected current can be used. Stigmator controls can be adjusted similarly to reduce astigmatism. The scan of control settings can be performed concurrently with sweeping the beam across a region of interest on the sample. Curved sweep patterns can be used. Energy measurements can be used as an alternative to current measurement. Applications to a nanoprobing workflow are disclosed.

Abstract: Beam intercept profiles are measured as a particle beam transversely scans across a probe. A current of beam particles, a detector intensity, or image pixel intensities can variously be measured to obtain the profiles. Multiple profiles are used to determine geometric parameters which in turn can be used to configure equipment. In one application, transverse beam intercept profiles are measured for different waist heights of the particle beam. Steepness of the several profiles can be used to determine a height of the probe as the height at which the profile is steepest. The known probe height enables placing the probe in contact with a substrate at another known height. In another application, transverse beam intercept profiles of orthogonal probe edges are used to position a beam waist, reduce spot size, or reduce astigmatism. Techniques are applicable to SEM, FIB, and nanoprobe systems. Methods and apparatus are disclosed, with variations.